BRPI1004970A2 - Mineral fluid paste and Method for preparing a mineral fluid paste - Google Patents

Abstract

MINERAL FLUID FOLDER, AND METHOD FOR PREPARING A MINERAL FLUID FOLDER. A new class of compounds, ie diamino alcohols, is described, together with a process for their production and use as rheology modifiers in high solid mineral slurries such as kaolin clay slurries.

Description

"MINERAL FLUID FOLDER, AND METHOD FOR PREPARING A MINERAL FLUID FOLDER" Field of the Invention

The present invention relates to a new class of compounds, i.e. diamino alcohols, a process for producing them, and their use as rheology modifiers in higher solid mineral slurries. Background of the Invention

Single amine compounds are known to provide neuralizing, dispersing and hardening properties when added to coatings, mineral slurries and epoxy formulation. Methods for making single amine compounds are well documented and known in the art and when the goal is to prepare primary amines, preferred routes often involve intermediate nitroalcohol compounds. For various reasons, it should be advantageous to have compounds with more than one amino group and volatile organic compound ("VOC") content.

Volatile organic compounds are organic chemical compounds that have vapor pressures high enough under normal conditions (ie 1 atmosphere and 25 ° C) to significantly vaporize and enter the atmosphere. These include a variety of chemicals, many of which have adverse health effects and are emitted by a wide variety of products that include but are not limited to: paints and varnishes, paint strippers, cleaning supplies, pesticides, building materials. and furniture, office equipment such as copiers and printers, correction fluids and carbonless copier paper, graphic and craft materials including glues and adhesives, permanent markers and photographic solutions. Minimizing VOC content has become a focus of public attention as well as government regulation.

Processes for the manufacture of intermediate nitroalcohol compounds are known and typically involve the reaction of nitroaldol (Henry's reaction) between nitroalkanes and aldehydes. There is occasional reference to the preparation of dinitro alcohols involving a Michael tandem addition and Henry's reaction of a nitroalkane with an α, 33-unsaturated aldehyde. For example, see "Secondary dinitro alcohols," Smith, Curtis W. (Shell Development Co.) 1949 and US Patent No. 2,475,996, which describes the manufacture of 2,5,6-trimethyl-2,6-dinitro nitro alcohol. 3-heptanol. This nitro alcohol is also preferred as an intermediate for the manufacture of a vasopeptidase inhibitor, as discussed in Janak Singh et al., Org. Lett, Efficient Asymmetric Synthesis of the Vasopeptidase Inhibitor BMS-189921. (2003), 5, 17, 3155-3158. In addition, the manufacture of the 2,6-dinitro-5-phenyl-heptan-3-ol nitro alcohol compound has been described in David St. Clair Black et. al. Australian Journal of Chemistry, 1976, 29 (11), 2511. Also well established, nitro alcohol compounds can be easily converted to amino alcohol compounds by hydrogenation with hydrogen in a suitable catalyst, for example Raney nickel or a catalyst. based on platinum or palladium (Pt or Pd in elemental form or as oxides, with or without supports, eg carbon). Those skilled in the art are also aware that other reducing agents that will reduce nitroalkanes to primary amines include metal / acid combinations, for example iron / acetic acid and aluminum hydrides. Preferred reducing agents include hydrogen gas in combination with any of the catalysts: Raney nickel, platinum or palladium.

Diamino alcohol compounds and their uses, on the other hand, are not commonly represented in the prior art.

The diamino alcohol compounds described herein will perform excellently as dispersants in mineral slurry systems, particularly in aqueous kaolin clay slurry having high solids content (i.e. more than 50 wt% solids) while maintaining fluidity required for handling. Calcined kaolin is an anhydrous aluminum silicate produced by the calcination (heating) of ultrafine natural kaolin material at high temperatures (700 ° C to 100 ° C) in a greenhouse. The calcination process whitens and hardens, improves electrical properties and alters the size and shape of kaolin particles. Calcined kaolin is useful for improving the thermal properties of agricultural films, improving the electrical performance of polyvinyl chloride cable, providing a functional filler in thermoplastic materials and as an additive for improving opacity in paints.

To date, polyacrylate salts have been used as dispersing agents in mineral slurries, such as kaolin clays, to communicate flowability, as the system will not flow in the absence of a dispersing agent. Polyacrylate salts have good handling and safety characteristics, but only allowed limited dispersion capacities such as solids content to be increased. Single diamines such as ethylenediamine have rheological limitations when higher solid loads are encountered, while longer chain diamines become highly colored and have a very offensive odor. Simple amino alcohols, such as 2-amino-2-methyl-1-propanol (AMP), do not have a high degree of adsorption to the calcined clay surface and have low efficiency as simple surface treatments or dispersants. There is a need for new dispersing agents which can provide aqueous kaolin clay slurry (preferably calcined kaolin clay slurry) have higher solids (> 50% solids). It is another object of this invention to provide superior solid aqueous calcined clay slurries that are sufficiently fluid and do not require multiple dispersing technologies that do not achieve the desired level of flowability in increased solids loading. Summary of the Invention

The present invention provides a mineral slurry comprising: (a) 40 to 55% by weight of water; (b) 45 to 58% by weight of a solid particulate clay material and (c) up to 2% by weight of a diamino alcohol compound having the formula:

-CH 2 OH; R 1 is independently hydrogen, alkyl or -CH 2 OH; alternatively R and R 1 may be linked together to form a cycloalkyl; R 2 is independently hydrogen, methyl, alkyl, phenyl or substituted phenyl; R 3 is independently hydrogen, alkyl, phenyl or substituted phenyl or -CH 2 OH; R 4 is independently hydrogen, alkyl or -CH 2 OH and alternatively R 3 and R 4 may be linked together to form a cycloalkyl; wherein all weight percentages are based on the total weight of the mineral slurry.

The solid particulate clay material may comprise clay, for example, without limitation kaolin clay. Detailed Description of the Invention

A new and useful class of amino compound, ie diamino alcohols, has been found, together with the processes for their manufacture. These compounds are produced by Michael Reaction and Nitroalkane Tandem Reaction with one or more α, β-unsaturated aldehydes and optionally post-reacted with an aldehyde such as formaldehyde. As a result, the diamino alcohol compounds produced have primary amino groups, preferably bonded to tertiary carbon atoms, with low volatile organic compounds (VOCs) content. These can be represented by the following formula:

R2 OH

wherein R is independently hydrogen, alkyl, aryl or wherein R is independently hydrogen, alkyl, aryl or -CH 2 OH; R 1 is independently hydrogen, alkyl or -CH 2 OH; alternatively, R 1 and R 1 may be linked together to form a cycloalkyl; R 2 is independently hydrogen, methyl, alkyl, phenyl or substituted phenyl; R 3 is independently hydrogen, alkyl, phenyl or substituted phenyl or -CH 2 OH; R 4 is independently hydrogen, alkyl or -CH 2 OH and alternatively R 3 and R 4 may be linked together to form a cycloalkyl.

The foregoing category of diamino alcohols includes various grades of polyalcohols ("polyols") as well as single diamino monoalcohols. The simplest diamino mono alcohols should have the following formula:

wherein R is independently hydrogen, alkyl, phenyl or substituted phenyl; R1 is independently hydrogen or alkyl; alternatively, R 1 and R 1 may be linked together to form a cycloalkyl; R2 is independently hydrogen, alkyl or phenyl or substituted phenyl; R3 is independently hydrogen, alkyl or aryl; R 4 is independently hydrogen or alkyl and alternatively R 3 and R 4 may be linked together to form a cycloalkyl.

The diamino mono alcohols of the present invention may be produced by the reaction of a nitroalkane and an α, β-unsaturated aldehyde that produces an intermediate dinitro alcohol compound. This reaction is typically operated at temperatures between 0 ° C and 100 ° C under atmospheric pressure, for example without limitation between 0 ° C and 50 ° C. Applicants have surprisingly and conveniently observed that this reaction sequentially precedes the addition of Michael of nitroalkane to the first occurring olefin, followed by the aldol (Henry) reaction in which the second nitroalkane is added to the aldehyde to produce a simple species of intermediate. monoalcohol dinitro.

The nitroalkane may be a primary or secondary nitroalkane having the formula:

NO2

where R is hydrogen, R1 is hydrogen, alkyl, phenyl or

substituted phenyl or wherein R is alkyl, phenyl or substituted phenyl, and R 1 is alkyl or R and R 1 may be linked together to form a cycloalkyl. For example, without limitation, nitromethane, nitroethane, 2-nitropropane, nitrocyclohexane, etc. They are all nitroalkanes suitable for use as starting materials for preparing the diamino alcohol compounds of the present invention. More particularly, the primary or secondary nitroalkane may be a C1 -C20 nitroalkane, a C1 -C10 nitroalkane or a C2 -C6 nitroalkane ·

Suitable α, β-unsaturated aldehydes have the following

formula:

H

wherein R is hydrogen, methyl (alkyl), phenyl or substituted phenyl. Unsaturated aldehydes include, but are not limited to, acrolein, crotonaldehyde, cinnamaldehyde, aromatic ring substituted cinnamaldehyde derivatives, etc.

The preceding sequential Michael-Henry reaction between nitroalkane and unsaturated aldehyde occurs in the presence of a suitable catalyst that includes, but is not limited to, organic bases such as 1,8-Diazabicyclo [5.4.0] undec-7-eno ( "DBU"), 2-dimethylamino-2-methyl-1-propanol ("DMAMP"), trimethylamine (TMA), dimethylisopropylamine (DMIPA), Ν, Ν, Ν ', Ν'-tetramethylguanidine (TMG), Verkade base , etc. Alternatively, inorganic bases such as potassium carbonate and sodium hydroxide may also be used as catalysts for the sequential Michael-Henry reaction described above.

Starting materials are provided in a typically 2: 1 molar ratio of nitroalkane to aldehyde. The reaction may be carried out with or without a solvent, according to the practitioner's preference. Suitable solvents include, but are not limited to tetrahydrofuran, 2-methyl tetrahydrofuran, dioxane.

When the desired product is a polyamino diamino compound, (1) nitroalkane is a primary nitroalkane and the process for producing the diamino polyalcohol compound further comprises, after reacting (1) primary nitroalkane and (2) α, β-unsaturated aldehyde, but before reducing the resulting nitro alcohol, the resulting nitro alcohol still reacts with (3) an aldehyde, such as formaldehyde, to form a polyalcohol dinitro compound, which is then further reduced. under hydrogenation conditions and in the presence of a catalyst.

More particularly, the production of diamino polyalcohol (polyol) compounds proceeds as follows: (A) reacting (1) a primary nitroalkane and (2) an α, β-unsaturated aldehyde to form a dinitroalcohol; (B) further reacts dinitroalcohol with (3) an aldehyde, such as formaldehyde, to form a polyalcoholic dinitro (e.g., a dinitroalcohol or dinitroalcoalcohol product) and (C) then further reduce the product. from dinitro polyalcohol to the corresponding diamino polyalcohol product under hydrogenation conditions in the presence of a catalyst. The reaction is carried out under conditions where Michael's addition of nitroalkane occurs more rapidly than Henry's reaction (ie temperatures between 0 ° C and 100 ° C under atmospheric pressure, for example, without limitation, between 0 ° C and 50 ° C), allowing sequential reactions to produce polyalcohol dinitro. (1) Nitroalkane and (2) aldehyde are supplied at a 2: 1 molar ratio during the first reaction step that produces dinitro alcohol. The primary nitroalkane may be a primary C1-C20 nitroalkane, for example, without limitation, a primary C1 -C20 nitroalkane. Α, β-unsaturated aldehyde may be selected from the group consisting of: acrolein, crotonaldehyde, cinnamaldehyde and aromatic ring substituted cinnamaldehyde derivatives.

Aldehyde, such as formaldehyde, occurs after completion of the reaction to form nitro alcohol has been confirmed (for example, as by analytical methods known to persons of ordinary skill in the art including, but not limited to, gas chromatography or liquid chromatography). high performance). The ratio of formaldehyde to dinitro alcohol is typically 2: 1 for this sequential reaction step. Again, this reaction may be carried out with or without the solvent, as preferred by the practitioner, such as, without limitation, tetrahydrofuran, 2-methyl tetrahydrofuran, dioxane.

The sequential Michael-Henry reaction described above has the following formula:

The subsequent reaction of dinitro alcohol with a second

The dinitro intermediate alcohol compound produced by

R4 R3

R R1

R2 OH

wherein R is independently hydrogen, alkyl, aryl, or -CH 2 OH; R 1 is independently hydrogen, alkyl, or -CH 2 OH; Alternatively, ReR may be linked together to form a cycloalkyl; R is independently hydrogen, methyl, alkyl, phenyl or substituted phenyl; R 3 is independently hydrogen, alkyl, aryl, or -CH 2 OH; R 4 is independently hydrogen, alkyl, or -CH 2 OH and alternatively, R 3 and R 4 may be bonded together to form a cycloalkyl.

In a particular embodiment the nitroalkane is 2-nitropropane and the unsaturated α, β-aldehyde is crotonaldehyde or cinnamaldehyde, which may produce a dinitro monoalcohol compound.

The dinitro alcohol intermediate, whether mono- or polyalcohol, is then further reduced under hydrogenation conditions in the presence of a suitable catalyst to produce the desired diaminoalcohol comprising two amino groups, each of which is attached to a tertiary carbon atom. . Suitable hydrogenation catalysts include, without limitation, Raney nickel, or a platinum or palladium-based catalyst (for example, platinum or palladium in elemental form or as oxides, with or without supports, for example, carbon). Other suitable reducing agents include, without limitation, metal / acid combinations, for example iron / acetic acid and aluminum hydrides. An example of a suitable hydrogenation catalyst system for use in accordance with the present invention is hydrogen gas in combination with either Raney nickel, platinum or palladium.

Hydrogenation of dinitro alcohol to produce diaminoalcohol may be carried out at pressures between 100 and 1000 pounds per square inch ("psi") (6.89 and 68.95 bar) and temperatures between 30 ° C and 100 ° C. A solvent may be used, such as, without limitation, tetrahydrofuran or methanol.

The resulting diamino alcohol compounds provide improved characteristics when used as dispersants in mineral slurries, such as clay slurries. For example, the novel diamino alcohol compounds of the present invention are effective dispersing agents for kaolin clay slurry, particularly kaolin clay slurry. These previously unknown multifunctional amino alcohols are low VOC and low odor, and when applied as dispersing agents by calcined clays, these materials enable the dispersive capabilities that leave improved solid fillers of aqueous slurries while maintaining desirable flowability at increased solid levels, without the application of additional dispersing technologies.

Calcined kaolin-containing clay is typically obtained by heating a water-kaolin-containing clay in an oven or similar apparatus. Typically total calcination occurs at a temperature close to or greater than 900 ° C. Kaolin-containing clay may include, without limitation, any raw, processed or partially processed kaolin clay. For example, kaolin clay may be a total or partial raw kaolin clay. In addition, the raw clay may comprise gray clay, or cream clay, and thus the raw clay may be a combination of clays and may be a soft or hard clay. Crude clay may contain an organic substance (ie raw ash) or may substantially lose the organic substance (ie cream, brown raw, light brown or red). Other materials may also be present in water kaolin-containing clay, such as one or more of silica, crystalline silica, or any other material, compound, or composition observed or used in the ceramic body material.

Additionally, the kaolin used in any of the obtained methods may be a fractionated clay having a particle size distribution that has been modified or aggregated, such as by mechanical methods or by alternative methods such as chemical fractionation or aggregation, in which the methods are well known in the art. Fractionation may be performed at any desired step in the method, such as before or after calcination of the kaolin-containing clay.

Additionally, clay (or crude), kaolin or other clay may be ground, for example, delaminated to modify its particle shape and / or size. Delamination methods are well known in the art. Additionally, modification of a resultant at least partially calcined kaolin can be made, for example, by grinding. Grinding procedures are well known in the art and may include, for example, chemical grinding or friction grinding.

According to one embodiment of the present invention, the calcined clay pigment in its form may be the surface treated by the addition of up to 2% by weight of the diamino alcohol compounds based on the total weight of a clay pigment. in a simple mechanical mixing operation. Alternatively, the dry calcined clay pigment may be the surface treated by any means generally known or developed by those of ordinary skill in the art (e.g. spray drying, blending, etc.). The treated calcined clay is then added to stirring water to form a slurry, which can then be used in any number of applications including but not limited to coatings and paint formulations, melting cap forming, paper fillers and plastic additives. .

A mineral slurry according to one embodiment of the present invention comprises (a) 40 to 55% by weight of water; (b) 45 to 58% by weight of a solid particulate clay material and (c) up to 2

% by weight of a diamino alcohol compound having the formula:

R4 R3 R R1

H2N

R2 OH

wherein R is independently hydrogen, alkyl, aryl, or CH 2 OH; R 1 is independently hydrogen, alkyl, or -CH 2 OH; alternatively, Re R 1 may be attached together to form a cycloalkyl; R 2 is independently hydrogen, methyl, alkyl, phenyl or substituted phenyl; R 3 is independently hydrogen, alkyl, phenyl or substituted phenyl, or -CH 2 OH; R 4 is independently hydrogen, alkyl, or -CH 2 OH and alternatively, R 3 and R 4 may be bonded together to form a cycloalkyl;

wherein all weight percentages are based on the total weight of the mineral slurry.

The solid particulate material may comprise clay such as, without limitation, kaolin clay, raw or uncalcised, colored or not.

In another embodiment of the present invention is a method for preparing a mineral slurry having greater than 50 wt% solids content based on the total weight of the mineral slurry comprising the combination (a) 40 to 55 wt%. water weight; (b) 45 to 58% by weight of a solid particulate clay material and (c) up to 2% by weight of the novel diamino alcohol compound described above.

EXAMPLES

Example 1

Synthesis of 2,5,6-trimethyl-2,6-dinitroeptan-3-ol (dinitro alcohol intermediate) NO2

H

A 3-neck round-bottom flask equipped with a stir bar, thermolink, nitrogen inlet drip funnel and the condenser was charged with 2-nitropropane ("2-NP") (50 g, 0.56 moles, 5.0 equivalents) and catalytic amount of DBU. The yellow solution was mixed under nitrogen for about thirty minutes. To this mixture was added crotonaldehyde (7.9 g, 9.2 mL, 0.112 mol, 1.0 equivalent) to the drops over a period of twenty minutes. The addition of crotonaldehyde was done under three different conditions as follows and all of these produced the same results.

Conditions:

(The). Add crotonaldehyde to the 2-NP / DBU mixture which is at -30 ° C and warmed to room temperature.

(B). Add crotonaldehyde to the 2-NP / DBU mixture which is at 20 ° C and warmed to room temperature.

(ç). Add crotonaldehyde to the 2-NP / DBU mixture that is at room temperature.

In each case, after complete addition, the reaction was stirred for approximately 5 to 6 hours at room temperature. During this period, white solid removed from solution. At this point, GC analysis showed the absence of any crotonaldehyde in the reaction mixture. After allowing the reaction mixture to stir overnight at room temperature and under nitrogen, the white solid was vacuum filtered from the solution and the solid washed everywhere with water. The solid was dried in air followed by vacuum drying at 45 ° C. The total yield of the desired nitro alcohol was 72% (27.8 g). Nuclear magnetic resonance ("NMR") and liquid chromatography (LC) testing showed that the product was> 99% pure.

13 C NMR (CDCl 3): δ 14.1, 20.7, 22.5, 23.1, 23.6, 33.5, 37.9, 73.1, 91.8 and 92.1 ppm.

Synthesis of 2,6-diamino-2,5,6-trimethylteptan-3-ol (diaminoalcohol)

g of the above nitro alcohol was dissolved in 200 mL of methanol and autoclaved at 60 ° C using 14.2 g of RaNi 3111 as a catalyst and at 600 psi pressure. After work that includes the

Catalyst filtration and methanol removal, approximately Ilg (59% yield) of the lower viscous colorless / light green liquid was obtained. NMR and gas chromatography mass spectroscopy ("GC-MS") analysis confirmed the presence of the desired amino alcohol. Chemical ionization mass spectroscopy (Cl-MS) showed [M + H] 189 and GC showed the purity of the material to be 94%. The boiling point of the material was approximately 1250 ° C at 135 ° C at 5.1 torr. The VOC of the material as determined by the modified EPA 24 method is 40%. The pKa of amines was 10.12.

13 C NMR (CDCl 3): δ 16.8, 25.2, 27.9, 30.8, 34.7, 42.2, 51.8, 52.8 and 77.3 ppm.

Example 2

Synthesis of 6-methyl-3,7-dinitrononan-4-ol (dinitro alcohol intermediate)

^ / NO2 Jo * f> *

.................................... u \ Ύί

H * CH3 OH I

A 3-neck round bottom flask equipped with a stir bar, thermolink, nitrogen inlet drip funnel and the condenser was charged with 2-Nitropropane (50 g, 0.56 mol, 5.0 equivalents) and quantity catalytic analysis of DBU. The deep yellow solution was mixed under nitrogen for about thirty minutes. To this mixture was added crotonaldehyde (7.9 g, 9.2 mL, 0.112 mol, 1.0 equivalent) to the drops over a period of twenty minutes. The addition of crotonaldehyde in this case was done at room temperature and during the addition, exotherm of about 12 ° C to 15 ° C was observed. After complete addition, the reaction was stirred at room temperature for 6 hours. In this period, GC analysis showed the absence of crotonaldehyde from the mixture. The reaction was allowed to stir at room temperature overnight and high performance liquid chromatography (HPLC) analysis showed only two peaks corresponding to the excess I-NP and desired product (ICA + 2NP adduct). ). Excess I-NP was removed by vacuum distillation and the resulting orange viscous liquid was subjected to hydrogenation. This material was about 37.2 g total weight however it still has some remaining I-NP.

Synthesis of 3,7-diamino-6-methylnonan-4-ol (diaminoalcohol intermediate) NO2

H2, Raney Nickel

CH3 OH '1 CH3 OH

37.2 g of the above nitro alcohol was dissolved in 50 mL of methanol and hydrogenated under hydrogen in the autoclave at 60 ° C, using 14.3 g of RaNi 3111 as a catalyst and at 600 psi pressure. After work including catalyst filtration and methanol removal, approximately 18g (64% yield) of the lower viscous yellow liquid was obtained. GC-MS analysis confirmed the presence of the desired amino alcohol. Cl-MS showed [M + H] = 189 and GC showed the purity of the material to be 50%. The remaining were the lower boiling materials. The pKa of amines was 9.85. Example 3

Synthesis of 2,6-dimethyl-2,6-dinitro-5-phenyleptan-3-ol (dinitro alcohol intermediate)

MO5

A 3-neck round bottom flask equipped with a stir bar, thermolink, nitrogen inlet drip funnel and the condenser was charged with 2-Nitropropane (101.1 g, 1.14 mol, 6.0 equivalents) and catalytic amount of DBU. The yellow solution was mixed under nitrogen for about twenty minutes. To this mixture was added trans-cinnamaldehyde (25.0 g, 0.19 mol, 1.0 equivalent) over a period of twenty minutes. During the addition of trans-cinnamaldehyde to nitro paraffin, an exotherm of approximately 22 ° C was observed. After complete addition, the reaction mixture was heated at 50 ° C for 4 hours. After the heating period, the mixture was allowed to cool slightly at room temperature. When the reaction mixture temperature reached 36.8 ° C, the light yellow solid was removed from the solution. The solid was filtered through a Buchner funnel and washed everywhere with pentane and ether. The white powder was allowed to dry under vacuum for 1 hour. The total yield of the desired nitro alcohol was 62% (36 g). NMR showed that the product was> 99% pure. 1H NMR (CDCl3): δ 1.45-2.27 (m, 15H), 3.52-3.54 (m, 1H), 3.67-3.74 (m, 1H), 7.17- 7.34 (m, 5H), 13CRMN (CDCl 3): δ 20.8, 22.4, 23.2, 25.8, 31.3, 50.3, 72.9, 91.5, 91.6 , 128.1, 128.7, 129.4, 136.6 ppm.

Synthesis of 2,6-diamino-2,6-dimethyl-5-phenylptan-3-ol (diaminoalcohol)

RaNi1Hg

NOp

50 g of the above nitro alcohol was dissolved in 300 ml of methanol and hydrogenated in the autoclave at 60 ° C using 24.3 g of RaNi 3111 as a catalyst and at 600 psi pressure. After work including catalyst filtration and methanol removal, approximately 40 g (68% yield) of the high viscous colorless / light yellow liquid was obtained. NMR and GC-MS Analysis confirmed the presence of the desired amino alcohol. Cl-MS showed [M + H] = 251 and GC showed the purity of the material to be 78% straight from the autoclave. The rest of the material is seen as a monoaduct obtained from Henry's reaction reversal. The mixture was purified by vacuum distillation. Approximately 96.2% purity of the desired material was obtained. The boiling point of the material was approximately 150 ° C to 160 ° C to 5.0 torr. The pKa of amines was 9.65. The VOC of the material as determined by the modified EPA 24 method is 4.4%. 1H NMR (CDCl3): δ 0.91 to 0.99 (m, 12H), 1.67-1.81 (m, 3H), 2.71-2.76 (m, 2H), 7.08- 7.23 (m, 5H), 13 C NMR (CDCl 3): δ 24.6, 27.9, 28.3, 29.8, 31.6, 51.8, 52.6, 54.2, 75, 9, 126.3, 127.8, 129.4, 142.0 ppm.

Volatile Organic Content (VOC). VOC is measured following the modified EPA 24 method. The VOC was measured only by the clean amine and the totally unformulated system. The amines are weighed in a crucible and kept in an oven for 1 hour at 105 to 110 ° C. Percent weight loss is related to VOC, corrected for water content in a sample that can be measured by Karl Fisher titration.

Example 4

Mineral fluid paste

2,6-Diamino-2,5,6-trimethylethylptan-3-ol prepared in Example 1 was used as a rheology stabilizer by an aqueous kaolin suspension as follows. A kaolin control slurry was prepared by first mixing water with Dispex N40V (commercially available polyacrylate dispersant from Allied Colloids) in a mixing shaker container. For this mixture, the dried untreated kaolin pigment was added under stirring to a suitable solid and melt level typical of calcined clay slurry as referenced as the control in the table below. The test slurries were prepared using dry kaolin pigment which was first treated by simply mixing the pigment in a container with the diamino alcohol. This operation consists of mixing the kaolin with diamino alcohol in a container that was covered and placed in a roller mill for 8 hours to allow the diamino alcohol to properly treat the kaolin surface. The treated calcined clay was then incrementally added to a container containing stirring water. Viscosity values were recorded at 1% of incremental kaolin dosages above 50% of solid loads. The data show that a minimum of 2% increase in solids is obtained while maintaining the fluidity of the slurry at comparable viscosity.

Table - Performance of CROT-AMP-NH2 in calcined kaolin clay

Clay solids (% by weight) Viscosity cP, 100 rpm Control (Dispex N40V only) Treated by Diamine (without Dispex N40V) Test 50.0 41 36 dilator versus control - slightly lower 51.0 46 40 52.0 54 44 53 .0 58 50 54.0 64 55

Claims (9)

1. Mineral fluid paste, characterized in that it comprises: (a) 40 to 55% by weight of water; (b) 45 to 58% by weight of a solid particulate clay material and (c) up to 2% by weight of a diamino alcohol compound having the formula: wherein R is independently hydrogen, alkyl, aryl or -CH 2 OH; R 1 is independently hydrogen, alkyl or -CH 2 OH; alternatively, R and R j may be linked together to form a cycloalkyl; R 2 is independently hydrogen, methyl, alkyl, phenyl or substituted phenyl; R 3 is independently hydrogen, alkyl, phenyl or substituted phenyl or -CH 2 OH; R 4 is independently hydrogen, alkyl or -CH 2 OH and alternatively R 3 and R 4 may be linked together to form a cycloalkyl; wherein all weight percentages are based on the total weight of the mineral slurry. Mineral slurry according to claim 1, characterized in that the solid particulate clay material comprises clay. Mineral fluid paste according to Claim 1, characterized in that the clay comprises kaolin clay. Mineral slurry according to claim 1, characterized in that R, R1, R2, R3 and R4 are each methyl. Mineral fluid paste according to Claim 1, characterized in that R, Rb, R3 and R4 are each methyl. R2 is phenyl. 6. Method for preparing a mineral slurry having more than 50% by weight solids content, based on the total weight of the mineral slurry *, comprising combining: Λ y 5 (a) 40 to 55 % by weight of water; (b) 45 to 58% by weight of a solid particulate clay material and (c) up to 2% by weight of a diamino alcohol compound having the formula: wherein R is independently hydrogen, alkyl, aryl or -CH 2 OH; R 1 is independently hydrogen, alkyl or -CH 2 OH; alternatively R and R 1 may be linked together to form a cycloalkyl; R 2 is independently hydrogen, methyl, alkyl, phenyl or substituted phenyl; R 3 is independently hydrogen, alkyl, phenyl or substituted phenyl or -CH 2 OH; R 4 is independently hydrogen, alkyl or -CH 2 OH and alternatively R 3 and R 4 may be linked together to form a cycloalkyl; wherein all weight percentages are based on the total weight of the mineral slurry. Method according to claim 6, characterized in that the solid particulate clay material comprises kaolin clay. A method according to claim 6, characterized in that R, R 1, R 2, R 3 and R 4 are each methyl and R 5 is hydrogen. A method according to claim 6, characterized in that R, Rh R 3 and R 4 are each methyl, R 2 is phenyl and R 5 is hydrogen.